Snap fastener

ABSTRACT

A snap fastener stud (S) for accommodating receivers (R) of varying thickness has a generally pear-shaped head with latching and retaining seats (38 and 40) therebeneath on opposite sides of the stud with the retaining seat having a radius of curvature (t) substantially greater than the radius of curvature (r) of the confronting surface of the receiver (R). In a modification the stud is capable of receiving a plurality of receivers (R 1  and R 3 ). The receivers may be formed with an annulus (72) which is separate from the portions (86 and 88) which are crimped to the fabric (F). The stud (S) has ribs (116) for preventing rotation on a surface on which the stud is mounted and a saddle shaped adapter (110) enables mounting of the stud on a cylindrical support (TF).

RELATED U.S. APPLICATION DATA

This application incorporates by reference U.S. Pat. Nos. 4,577,376,4,646,399, and 4,409,706.

1. Field of Invention

This invention relates to snap fasteners intended to connect togethertwo or more members with which the fastener is associated.

2. Background of Invention

U.S. Pat. Nos. 4,577,376, 4,646,399 and 4,409,706 disclose snapfasteners which represent substantial improvements over the conventionalDOT® fastener, or any other commercially available snap fasteners. Theseimproved fasteners essentially comprise a stud connected to one part anda grommet-like receiver connected to the other part, for example afabric layer. The design of the stud is such that the receiver and studmay be snapped together and cannot be seperated unless a particular edgeof the receiver is lifted relative to the stud. Experimentation hasshown that several improvements in refining the design are desirable tomake a more universally acceptable product.

SUMMARY OF THE INVENTION

The snap fastener herein disclosed has a stud so designed that it willaccept the receiver with either side "facing down" and wherein thereceiver may be of various thicknesses (as when mounted on variousnumbers of fabric layers) and yet will lock the parts together with anaudible and tactile snapping action. This is accomplished in oneembodiment by a redesign of the receiver seats beneath the lockingshoulder and retaining lobe. Both seats are substantially "opened up" ascompared with the seats in U.S. Pat. No. 4,646,399 and the receiver seatbeneath the locking shoulder is generally concave with a radius ofcurvature substantially greater than the radius of curvature of theconfronting surface of a receiver whereby the stud will accommodatereceivers of varying thickness or profile.

In another embodiment the stud has receiver seats capable of havingmultiple receivers mounted thereon. This has particular utility when itis desired to overlap the margins of two covers. For example in bringingtogether the edges of boat covers it may be desired to place themarginal edges over common studs.

In another improvment in the stud design, the base of the stud isprovided with means for resisting rotation of the stud on the member, towhich it is secured. Furthermore, the base of the stud may be configuredto serve an orienting function not only in mounting the stud on themember to which it is to be permanently secured, but also in automatichandling machines during stud manufacture or application.

As disclosed herein, adapter means are shown permitting mounting of thestud on a cylindrical surface such as an awning frame or a stanchion andyet the stud will not rotate out of position thereon under conventionalloading.

In a further improvement, the receiver is designed to have an insidediameter and profile independent of the attachment of the receiver tothe fabric material upon which it is to be mounted, and also wherein thereceiver may have a wear surface at its inside diameter different thanthe characteristics of the material of which the remainder of thereceiver is fabricated. In this connection, the strength of the receiveri.e., distortion resistance, may be substantially improved withoutfabricating the entire receiver of different or stronger materials.

Details of the fastener design giving rise to these desirable advantagesare more fully disclosed hereinafter.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a top or plan view of a snap fastener stud embodying theinvention;

FIG. 2 is a front elevation of the stud looking in the direction ofarrow 2 in FIG. 1;

FIG. 3 is a side elevation of the stud of FIG. 1;

FIG. 4 is a bottom view of the stud of FIG. 1;

FIG. 5 is a cross-sectional view taken along the line 5--5 of FIG. 3;

FIG. 6 is a side elevation similar to FIG. 3 and showing a receivermounted thereon with an exaggerated outline of receivers of varyingthickness in relation to the stud;

FIG. 7 is a side elevation similar to FIG. 3 but showing five planesextending from the center of curvature of the receiver seat beneath theretaining lobe to various points on the latching shoulder;

FIGS. 8-12 inclusive are cross-sectional views through the stud takensubstantially on planes 8-12 of FIG. 7;

FIG. 13 shows a piece of fabric having a hole therein ready for areceiver to be mounted therein;

FIG. 13A is a modified form of the stud wherein the receiver seatbeneath the latching shoulder is straight rather than concave;

FIG. 14 is a cross-sectional view through a modified receiver showing awear annulus whose inside diameter is independent of the attachment ofthe receiver to the fabric;

FIG. 15 depicts in exploded view a setting tool for assembling thereceiver of FIG. 14 to a fabric member;

FIGS. 16 and 17 show mounting of a receiver on a stud;

FIG. 18 shows a stud for accepting multiple receivers;

FIG. 19 is a tubular rivet element particularly useful in securing astud to fabric material;

FIG. 20 shows the mounting arrangement for a stud on the fabricmaterial;

FIG. 21 is a top or plan view of a stud adapter for use with cylindricalsurfaces to facilitate mounting of the stud of FIG. 1 thereon;

FIG. 22 is a front elevation of the stud adapter of FIG. 21;

FIG. 23 is a side elevation of the stud adapter of FIGS. 21 and 22; and

FIG. 24 is a cross-sectional view through the assembly of a stud adapterand a stud, mounted on a cylindrical support.

BRIEF DESCRIPTION OF PREFERRED EMBODIMENTS

In FIGS. 1-3, 6, 16 and 17, a stud S mounted on a member 24 to befastened, is intended to cooperate with a receiver R which is mounted onone or more layers of a fabric material F. The stud is preferably madeof plastic, such as nylon type 66, with an ultraviolet inhibitor. Thestud is generally cylindrical having a head 20 at one end and isintended to be mounted in upstanding relation at its opposite or baseend 22 on the member 24. The member 24 may be rigid or may be a flexiblefabric as hereinafter mentioned. The stud may have a hole 26 extendingaxially therethrough with a flat bottom counterbore 28 opening throughthe head. As shown in plan view in FIG. 1, the head is somewhatpear-shaped to provide a retaining or locking lobe 30 and an oppositelatching shoulder 32. The retaining lobe 30 and latching shoulder 32 aredisposed at opposite longitudinal sides of the stud, and blend smoothlyinto transversely disposed shoulders 34 and 36.

Encircling the stud beneath the shoulders 32, 34 and 36 and the lobe 30are receiver seats 38, 40, 42 and 44 which cooperatively form acontinuous surface of varying shape as shown in FIGS. 2, 3 and 5. Thebottom wall or surface of these seats is formed on considerably largerradii than in the case of the stud shown in U.S. Pat. No. 4,646,399 andthe stud can thereby accommodate a receiver of varying thickness as, forexample, receivers mounted on between one and four or even fivethicknesses of fabric. More specifically, as shown in FIGS. 3 and 6, inconnection with the receiver seat 38 (herein termed the locking seat),beneath the locking lobe 30, the seat is concave and is formed on aradius of curvature t that is substantially greater than the radius ofcurvature r of the confronting receiver. In FIG. 6 there is shown insolid outline at R a receiver mounted on a single layer of fabric F. Asthe number of fabric layers on which receivers are mounted increases,the thickness of the receivers also increases as shown in exaggeratedform at R₂, R₃ and R₄ representing receivers mounted on respectivelytwo, three and four layers of fabric. Thus, as used herein, whenindicating that the radius t of locking seat 38 (see FIG. 3) issubstantially greater than the thickness of the receiver, the contextrefers to a radius to which is sufficiently greater than the thicknessof the receiver that the stud will accomodate receivers mounted on fromat least one to four fabric layers.

In a representative embodiment utilizing receivers similar to number 3grommets, the thickness through the receiver was measured as follows:

    ______________________________________                                        # of Fabric Layers                                                                            Thickness of Receiver                                         ______________________________________                                        1               0.180"                                                        2               0.184"                                                        3               0.188"                                                        4               0.215"                                                        ______________________________________                                    

The radius t of the locking seat 38 beneath the locking lobe 30 is onthe order of 0.130". Thus, the radius t of the seat 38 should be greaterthan about 0.6 times the maximum thickness of the receiver wherereceivers of varying thickness but essentially constant inside diameter(hole diameter) are utilized. This relationship of seat radius toreceiver thickness appears desirable for enabling receivers mounted onvarying numbers of fabric layers to snap with proper action on the stud.

The prior art studs shown in U.S. Pat. Nos. 4,577,376, 4,646,399 and4,409,706 were not designed to accommodate receivers of varyingthickness.

The surface of receiver seats 42 and 44 as shown in FIG. 2 are formed onan even greater radius and constitute a generally smooth transitionaround the stud beneath the head to seat 40 beneath the latchingshoulder. This latter seat, herein termed the latching seat, may beslightly concave being formed with a radius of curvature greater thanthe radius of curvature r of the locking seat as shown in FIG. 3. Asshown at 40a in FIG. 13 this latching seat may be essentially "straight"from the edge of shoulder 32a toward the base 22a or in other words,substantially coaxial with the axis of the stud.

The root dimension of the groove forming the seats 38-44 is depicted bythe dot-dash line 46 in FIGS. 2 and 3 and undulates vertically as shown.A section taken along this root dimension is shown in FIG. 5 at 46 asbeing nearly circular. In FIG. 3 the dash line 48 is taken on a planeperpendicular to the stud axis X-X and intersects the root 46 at seats38 and 40. The profile of this plane is shown in somewhat exaggeratedform in FIG. 5 at 48. It will be noted from FIG. 5 that the transversedimension TD across the stud at line 48 is greater than thecorresponding dimension at line 46. It is feasible to establish thedimension TD so that it is substantially equal to the internal diameterof a receiver mounted on the stud and thus, a receiver R disposed on thestud as shown in phanton in FIG. 3, will be internally supportedtransversely against collapse by the stud dimension TD as loading forceson the receiver in the longitudinal direction A-B (see FIG. 1) tend todeform the receiver.

The base end 22 of the stud is provided with means for resistingrotation of the stud about its axis X-X. Such means may take variousforms, but is herein shown as comprising uniformly arranged radiatingridges 50. The ridges project below the base end surface 52 and may beeither of V-shape with a sharp apex or slightly rounded as shown inFIGS. 2 and 3. In either event the ridges are intended to slightlypenetrate the underlying member 24 to prevent rotation of the studrelative thereto when the stud is pulled tightly thereagainst. Whileeight such ridges are shown, a greater or lesser number may be utilizedas desired.

The plan view of the base is best shown in FIG. 4 and is provided withopposed parallel straight sides 56 and 58, a straight back edge 60beneath the locking shoulder 32 and a smoothly curving front edge 62.The rear corners may be beveled as at 64 and 66. Not only does thisshape serve an orienting function in placing the stud in proper rotatedposition on the member 24 to which it is to be fastened, but such shapemay also be utilized during manufacture for orienting the studs inautomatic feeding and packaging machines.

At the rear side of the head at the top of the locking shoulder 32, thehead is smoothly curved as at 68 to provide a receiver camming surfaceoperable to internally stretch the receiver R slightly within itselastic limit to permit the receiver to snap over the stud as shown inthe sequence in FIGS. 16 and 17. The receiver to be used with the studmay be of the type disclosed in the aforesaid patents. A number 3grommet is an appropriate receiver for many applications. Such a grommetwhen formed of nickel plated brass or stainless steel is suitable formarine applications, the latter being particularly desirable for harshenvironments where relatively high stress may be encountered. However,receivers formed of other materials, including plastic, may be quitefeasible.

In FIGS. 14, 16 and 17 a modified form of receiver is shown. Thisreceiver is intended to provide a receiver structure where the portion72 engaging the stud may be fabricated of a different material than someor all of the remaining portions of the receiver. Portion 72 is shown asan annulus of regular cross-section i.e., opposite sides present mirrorimages whereby either face 78 or 80 of the receiver will present thesame configuration to the stud. Accordingly, the receiver will lock withits characteristic snapping action whichever face is presented to thestud. Conventional number 3 grommets, for example, while useable withthe stud, often exhibit somewhat different snapping characteristicsdepending on which face is presented to the stud. This results becauseopposite faces are not mirror images and present slightly differentstructural configurations for engagement with the stud.

Uniformity of feel, sound and appearance may be desirablecharacteristics and the receiver embodiment shown in FIGS. 14, 16 and 17is intended to provide for such. The receiver includes cooperatinginterlocking portions 84 and 86 intended to overlie opposite faces of afabric member F circumjacent a hole H best shown in FIGS. 13 and 14. Thehole H is prestamped or otherwise formed in the fabric member F. Suchreceiver portions generally correspond to conventional grommet elementsand are intended to be crimped together with the fabric therebetweenthrough the use of cooperating dies as shown in FIG. 15 where the diemember 81 having a guide bore 87 cooperates with the die member 83having a guide nose 85 intended to enter the bore 87 holding the dies inproper registry. The receiver portions 84 and 86 define an aperturewithin which is disposed and locked the annulus member 72. The annulusmember cooperates directly with the stud. The shape and inside diameterof the annulus member 72 is essentially independent of the portions 84and 86 of the receiver and in particular essentially independent of thecrimping action of the receiver portions 84 and 86 as they are crimpedbetween the dies. Thus this structure insures uniformity of operationindependently of the crimping of the receiver members 84 and 86.

Annulus portion 72 has a smoothly curved inside diameter surface 79 (seeFIG. 14) and a generally cylindrical outside diameter surface 73exhibiting a medially disposed circumferential rib 82 for locking theannulus within the receiver portion 84. Receiver portion 86 cooperateswith receiver portion 84 to embrace the marginal edge of the hole H inthe fabric member F and the two portions are crimped together andagainst the fabric F as above mentioned and as shown in FIG. 15.Receiver portion 84 has an outer wall 88 whose outer marginal edge 90 iscurved over and crimped against or into the fabric F while its innermarginal edge is defined by a wall 92 disposed generally perpendicularto the outer wall 88 and provided medially with a circumferential groove94 for receiving the rib 82. During crimping of the receiver portions 84and 86 between dies 81 and 83 the inner marginal edge 92 is crimped overat the curl 96 to overlie receiver portion 86. During such crimping theinner marginal edge wall 92 is urged radially inwardly to tightly gripthe outside face 73 and the rib 82 of the annulus 72 thus securelylocking the annulus in the receiver.

The annulus may be formed of a solid material either of metal orplastic, the material selected being chosen for the particularcharacteristics desired, such as strength, resistence to environmentalconditions, wear resistance and the like. The annulus may be formed toprovide great strength and/or rigidity for applications where either orboth considerations are essential. Alternatively, the annulus may befabricated of sheet metal, such as stainless steel while the remainderof the receiver is formed of brass or the like. This may be desirable toprovide a receiver of great strength having the durability of stainlesssteel without the expense of forming the entire receiver therefrom.Other advantages of having a separate inner annulus will occur to thosestudying this design.

As shown in FIG. 15 the annulus 72 is intended to be captive in thereceiver portion 84 before the portions 84 and 86 are crimped together.Thus, the canvas man using this type of receiver will only deal with twopieces as is presently conventional in assembling grommets in canvas orsimilar fabric products.

In selecting the material for the inner annulus 72 and determining itsdimensional relationships to the stud, due consideration must be givento the necessity of having the annulus snap over and be locked on thestud as shown in FIGS. 16 and 17. Thus, the inside diameter of theannulus must be slightly undersized the shortest dimension of the studmeasured from the receiver seat 38 beneath the retaining lobe to theapex of the locking shoulder 32, the dimensional relationship being suchthat as the receiver is cammed down over the camming surface 68 theannulus will flex sufficiently within its elastic limit to snap over thelocking shoulder to be seated as shown in FIG. 17.

In FIGS. 7-12 there are shown several critical relationships between thestud and a receiver. Planes 8, 9, 10, 11 and 12 extend through thecenter of curvature C of locking seat 38. Plane 8 is shown in profile inFIG. 8. The receiver R is shown as having a circular opening R₈ whilethe profile of the stud S is slightly elongated thereby causing thereceiver to rest against the stud at opposite points 37 (on cammingsurface 68 and locking seat 36) but spaced from the stud slightly atopposite points 39 at sides 34 and 36 (see FIG. 2). As the receiver ispressed down the sloping camming surface 68 from plane 8 to plane 9, thereceiver is stretched between points 37a as shown in FIG. 9 andsimultaneously slightly narrowed at points R₉. The stud is also relievedat 39a at opposite sides to continue to afford space between the nowslightly narrowed receiver and the stud head. As the receiver continuesto be pushed down the camming surface 68 it reaches plane 10,illustrating in FIG. 10 the greatest elongation of the receiver; thereceiver being stretched within its elastic limits between points 37band by virtue of the relief of the sides of the stud head as shown inFIGS. 2 and 10 at 39b such elongation of the receiver is permitted. Thereceiver at plane 10 is virtually ready to snap on down the stud throughthe position of plane 11 where the receiver is beginning to recover fromits elongation as shown in FIG. 11 but still bears at points 37c againstthe stud and is still slightly spaced at 39c from the stud. At plane 12the receiver has assumed its original substantially circular conditionas shown in FIG. 12. The receiver may lightly bear, or even be slightlyspaced, from the stud at points 37d. At the sides 39d, the receivershould be only slightly spaced, if at all, or in light contact with thestud whereby the stud will offer internal transverse support for thereceiver under the influence of loading in the direction A-B (seeFIG. 1) thereby supporting the receiver against collapse during suchloading and preventing distortion beyond its elastic limit.

A critical dimension of the stud is the locking dimension LD shown inFIG. 3. This dimension lies in plane 10 shown in FIGS. 7 and 10. It maybe defined as the greatest thickness or dimension across the studbetween the locking seat 38 and the latching shoulder 32 lying in aplane intersecting the center of curvature C of the locking seat. Thelocking dimension in the preferred embodiment should be sufficientlygreater than the undistorted internal diameter of the receiver so thatthe receiver will be stretched to audibly snap on to the latching seatas the receiver is cammed down over the latching shoulder. At the sametime the locking dimension LD should not exceed the internal diameter ofthe receiver by such an amount that when the receiver is stretched overthe locking dimension the receiver is deformed beyond its elastic limit.Thus, the deformation of the receiver in moving from plane 8 throughplane 12 and back again should be within the elastic limit of thereceiver. As shown in FIG. 3, the least dimension E measured from theapex of the retaining lobe 30 to the latching seat should besufficiently greater than the internal diameter of the receiver that thereceiver cannot be tilted or lifted off the stud by lifting the edge ofthe receiver beneath the retaining lobe.

In FIG. 18 there is shown a modified form S₁ of the stud intended toreceive thereon at least two receivers R₁ and R₂ mounted on fabric F₁and F₂. In this embodiment the stud is generally similar to thatprevious described except the receiver seats 38_(a) and 40_(a) are ofgreater vertical dimension to accommodate the receivers. The head 20ais, as before, generally pear-shaped in cross-section similar to thatshown in FIG. 1 and has a locking lobe 30a and an oppositely disposedlatching shoulder 32a. The stud has a vertical bore 26_(a), a counterbore 28_(a) and is intended to be secured to a member 24_(a) by asuitable fastener such as a rivet, bolt, screw or the like, representedgenerically at 27_(a). The locking dimension LD shown in FIG. 18 is asbefore described in connection with FIGS. 3 and 7. The base of the studmay be provided with radially extending ribs 50_(a) as before describedto prevent rotation of the stud. This form of stud is particularlysuitable when, for example, it is desired to attach in overlappingrelation the edges of two oppositely extending sections of a boat coveror the like on a common stud.

In FIGS. 19 and 20 there is shown a tubular rivet 100 intended tocooperate with a stud of the type disclosed in this application or inthe aforesaid related patents. This rivet is intended to preventrotation of the studs in the fabric on which they are mounted, and maybe used with studs having or not having the radial ribs 50 and 50_(a).The rivet has a tubular shank 102 terminating at one end in a circularhead 104 having axially extending peripheral teeth 106 for engaging in afabric member F₃ as shown in FIG. 20 beneath the base 22_(a) of the studS₂. The stud S₂ is shown without the ribs 50, but such may be providedif desired. The opposite end of the rivet from the head 104 is crimpedover as at 108 to overlie and bear against the bottom 110 of the counterbore 28_(a) and lock the stud securely against the fabric F₃ squeezingthe same between the head 104 and the base of the stud. The frictionalengagement of the crimped end 108 against the bottom 110 of the counterbore is intended to prevent rotation of the stud on the fabric layer.Should there still be a tendency in a particular application for thestud to rotate, studs having the ribs 50 should be used. The teeth 106are sufficiently spaced circumaxially so that ribs 50 will fittherebetween such that the fabric will be gripped between the ribs andteeth to provide a particularly secure non-rotative attachment betweenthe stud and underlying fabric.

In FIGS. 21-24 there is shown an arrangement for mounting the stud on acylindrical surface such as a tubular frame TF. It is important in sucha mounting that the proper rotative orientation be maintained and thusthe stud must not be permitted to rotate. As disclosed, a stud mountingadapter 111 of saddle-shaped configuration has a semi-cylindricalopening 112 sized to mate with the tubular frame as shown in FIG. 17 anda flat stud mounting surface 114 provided with radially extendinggrooves 116 matching in configuration and arrangement the ribs 50 on thestud base. The adapter has a through aperture 118 intended to align withthe mounting hole 26 when the stud of FIGS. 1-5 is mounted on theadapter. A fastener such as a sheet metal screw 120 or a bolt, rivet orthe like, is extended through the stud, adapter, and into the tubularframe to tighten therein and lock the parts together. The ribs 50 on thebase of the stud cooperate with the grooves in the adapter to preventrotation of the stud. Thus the stud may be mounted on the tubularframework utilizing the adapter shown and will not rotate thereon.

We claim:
 1. A snap fastener assembly comprising, in combination;agenerally cylindrical stud having a head at one end and intended to bemounted in upstanding relation at its opposite end on a member to befastened; receiver seats disposed on opposite sides of the stud beneathsaid head; a latching shoulder on the head above one of the seats; aretaining lobe on the head above the opposite seats; said stud throughthe latching shoulder and retaining lobe being generally pear-shaped;the dimension of the stud measured from the apex of said lobe to theseat on the opposite side of the stud being grater than the dimension ofthe stud measured from the apex of said shoulder to the seat on theother side of the stud to lock a receiver in said seats beneath thehead; a receiver to be secured to a part to be fastened and having acircular aperture for reception over the stud with the surface of thereceiver at the aperture confronting the stud; and said receiver seatbeneath said lobe being generally concave and having a radius ofcurvature substantially greater than the radius of curvature of theconfronting surface of the receiver whereby the stud will accommodatereceivers of varying thickness.
 2. The invention defined by claim 1wherein the radius of curvature of the receiver seat beneath theretaining lobe is greater than about 0.6 times the maximum thickness ofreceivers to be accommodated.
 3. The invention defined by claim 1wherein said receiver seats have a dimension measured axially of thestud sufficient to accommodate a plurality of axially aligned andstacked receivers.
 4. The invention defined by claim 3 wherein theradius of curvature of the receiver seat beneath the retaining lobe isimmediately subjacent the lobe and the said seat is substantiallystraight for a distance beneath such curvature.
 5. The invention definedby claim 1, 2 or 3 wherein the receiver seat beneath said latchingshoulder is generally concave and has a radius of curvature greater thanthe radius of curvature of the opposite seat.
 6. The invention definedby claim 1, 2 or 3 wherein the receiver seat beneath said latchingshoulder extends substantially coaxially of the stud.
 7. A snap fastenerassembly comprising, in combination;a generally cylindrical stud havinga head at one end and intended to be mounted in upstanding relation atits opposite end on a member to be fastened; receiver seats disposed onopposite sides of the stud beneath said head; a latching shoulder on thehead above one of the seats; a retaining lobe on the head above theopposite seat; said stud, including the latching shoulder and retaininglobe having a continuous peripheral surface and being generallypear-shaped; the dimension of the stud measured from the apex of saidlobe to the seat on the opposite side of the stud being greater than thedimension of the stud measured from the apex of said shoulder to theseat on the other side of the stud to lock a receiver in said seatsbeneath the head; a receiver to be secured to a part to be fastened andhaving a circular aperture for reception over the stud; and thetransverse dimension of the stud lying in a plane perpendicular to thestud axis and intersecting the bottom of the receiver seats beneath theshoulder and lobe being substantially equal to the internal diameter ofthe receiver when seated on the stud in said seats to support thereceiver against collapse by loading forces thereon extending in thedirection of said longitudinal dimension.
 8. A stud assembly for a snapfastener for mounting on a cylindrical surface comprising, incombination:a generally cylindrical member having a head at one end anda base at the opposite end intended to be mounted in upstanding relationat its base on a member to be fastened; receiver seats disposed onopposite sides of the stud beneath said head; a latching shoulder on thehead above one of the seats; a retaining lobe on the head above theopposite seats; said stud, including the latching shoulder and retaininglobe, being generally pear-shaped; a saddle-shaped adapter for embracingthe cylindrical surface of the member on which the stud is to bemounted; said saddle-shaped member and said stud having aligned throughapertures whereby fastener means may be extended through the stud andadapter to cooperatively engage the cylindrical member for retaining thestud and adapter thereon; and means for preventing relative rotationbetween the stud and adapter.
 9. The invention defined by claim 8 inwhich said base and adapter have mating faces provided with cooperatingprojections and recesses for limiting relative rotation of the stud onthe adapter.
 10. A receiver for a snap fastener comprising, incombination:a receiver portion for overlying a fabric member and to besecured thereto; said receiver portion defining an aperture; saidreceiver portion having an annular groove at the aperture and extendingcircumferentially therearound and located substantially wholly withinthe aperture; and a continuous annulus member disposed in said apertureand radially interlocked with the receiver portion substantiallycoplanar with the fabric to provide a stud engaging surface for thereceiver.
 11. The invention defined by claim 10 characterized in thatsaid annulus member is provided with a peripheral rib for fitting insaid groove and trapping the annulus member within said aperture. 12.The invention defined by claim 10 wherein said annulus member is formedof a material different than the material of said receiver portion. 13.The invention defined by claim 10 wherein said receiver portion isformed of sheet material and said annulus is a solid relatively lessdistortable member.
 14. The invention defined by claim 10 wherein saidreceiver portion is formed of materials taken from the class comprisingbrass, stainless steel and plastic and the annulus member is found ofmaterials taken from the class comprising plastic and stainless steel.